PRIME B550M-K

    AMD B550 (Ryzen AM4) micro ATX motherboard with dual M.2, PCIe 4.0, 1 Gb Ethernet, HDMI/D-Sub/DVI, SATA 6 Gbps, USB 3.2 Gen 2 Type-A

    • AMD AM4 socket: Ready for 3rd Gen AMD Ryzen™ and 3rd Gen AMD Ryzen™ with Radeon™ Graphics Processors
    • Comprehensive cooling: PCH heatsink and Fan Xpert 2+
    • Ultrafast connectivity: Dual M.2, PCIe 4.0, 1 Gb Ethernet, USB 3.2 Gen 2 Type-A
    • 5X Protection III: Multiple hardware safeguards for all-around system protection
      Product Image
      TUF H370 Plus Gaming TUF H370 Plus Gaming
      • PS/2

      • 2 x USB 3.2 Gen 1

      • DVI-D

      • D-Sub

      • HDMI

      • 2 x USB 3.2 Gen 2

      • Realtek LAN

      • 2 x USB 3.2 Gen 1

      • 3 x Audio jacks

      • PCIe 4.0 x16
        ASUS SafeSlot Core

      • Audio Features
        ● LED-illuminated design
        ● Audio Shielding
        ● Premium Japanese
        audio capacitors
        ● Dedicated audio
        PCB layers

      • DIGI+ VRM & EPU

      • DDR4 support

      • AMD AM4 Socket

      • 2 x Front USB 3.2 Gen 1

      • 64Gb/s M.2 support
        PCIe 4.0 x4 & SATA mode

      • AMD B550 Chipset

      • 32Gb/s M.2 support
        PCIe 3.0 x4 & SATA mode

      • 4 x SATA 6Gb/s

      • 4 x Front USB 2.0

      ASUS Prime series is expertly engineered to unleash the full potential of 3rd Generation AMD Ryzen platform. Boasting a robust power design, comprehensive cooling solutions and intelligent tuning options, Prime B550 series motherboards provide daily users and DIY PC builders a range of performance tuning options via intuitive software and firmware features.

      Tune It Your Way

      Comprehensive controls form the foundation of the ASUS Prime series. The Prime B550 motherboard packs flexible tools to tune every aspect of your system, enabling you to tweak performance settings to perfectly match the way you work – maximizing your productivity.

      All-around Energy Efficiency

      With the Energy Processing Unit (EPU), you'll enjoy system-wide power savings. The EPU automatically optimizes power consumption and maximizes savings with Away mode.

      Flexible Cooling Controls

      Fan Xpert 2+ software provides comprehensive control over system fans. Auto-Tuning mode intelligently configures all parameters with a single click. There's also an Extreme Quiet mode that reduces chassis fan speeds to below the default minimum to keep your system whisper-quiet when performing light tasks. Fans can also be controlled via the UEFI BIOS.

      Precise Digital Power Control

      The Digi+ voltage-regulator module (VRM) delivers real-time control over voltage droop, automatically switching frequency and power-efficiency settings. It also allows you to fine-tune your CPU for ultimate stability and performance.

      Back to Tune It Your Way


      The renowned ASUS UEFI BIOS provides everything you need to configure, tweak and tune your system. It offers intelligently simplified options for PC DIY beginners, as well as comprehensive features for seasoned veterans.

      Advanced Tuning for Serious Tweakers

      An intuitive Advanced mode offered via the UEFI lets you take complete control. A built-in search feature makes it easy to find options, and various Advanced functions let you intelligently make nuanced adjustments so you can dial in performance just the way you want.

      Search Function
      Quickly and easily find the option or setting you need.

      ASUS User Profile
      Port configuration settings between different BIOS versions or share them with friends.

      Quick and Simple Setup

      EZ mode displays vital settings and stats and also offers guided wizards, drag-and-drop functionality, and one-click application of important settings — all to help you get your rig up and running in no time.

      Intuitive Graphical Fan Control
      Fine-tune individual fan settings simply by dragging a curve with the mouse.

      EZ XMP
      Improve DRAM performance with one click.

      Back to Tune It Your Way

      Cooler by Design

      Prime B550M-K is engineered with an array of hybrid fan headers and features comprehensive cooling controls that are configurable via Fan Xpert 2+ software or via the UEFI BIOS, ensuring your rig stays cool and stable under intense workloads.

      • Multiple Temperature Sources
      • Smart Protection
      • 4-Pin PWM/DC Fan
      • Each header can dynamically reference three thermal sensors. Fan Xpert 2+ allows you to map the temperature of supported ASUS graphics cards to optimize cooling for GPU- and CPU-intensive tasks.

      • A dedicated integrated circuit protects each fan header from overheating and overcurrent.

      • Each onboard chassis fan header supports PWM and DC mode.

      Back to Cool to the Core

      Build on a Solid Foundation

      Prime B550 motherboard provides all the fundamentals to boost daily productivity, so your system will be ready for action with stable power, intuitive cooling and flexible transfer options.

      ProCool Connectors

      Proprietary connectors augment the motherboard's link to the PSU with 8+4 pin connectors that pass 12 volts of power directly to the processors. The jacks feature solid pins that can handle more current than hollow-pin connectors.

      10+1 DrMOS Power Stages

      A VRM with 10+1 DrMOS Power Stages delivers the power and efficiency that the latest Intel processors demand.

      Back to Build on a Solid Foundation

      ASUS OptiMem II

      Revisions to the motherboard's trace routing provide the latest Intel processors with unrestricted access to memory bandwidth. ASUS OptiMem II technology carefully maps memory signal pathways across different PCB layers to reduce vias and adds shielding zones that significantly reduce crosstalk.

      Top layer – ground ring to prevent lateral interference

      ASUS OptiMem II benefits:

      • Improved memory stability and compatibility
      • Allows lower memory latencies at equivalent voltages
      • Improved memory frequency margin

      Motherboards with OptiMem II technology were tested with Synopsys HSPICE simulation software

      Back to Build on a Solid Foundation

      PCIe 4.0 M.2
      (up to 64 Gbps)

      Achieve speed with onboard M.2

      PCIe 4.0 M.2 Slot supports up to 22110 and provide NVMe SSD RAID support for an incredible performance boost. Create a RAID configuration with up to PCIe 4.0 storage device to enjoy the fastest data-transfer speeds on the 3rd Generation AMD Ryzen platform.

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      Intel® WiFi 6 AX200

      The Intel® WiFi 6 AX200 module is compatible with the 802.11ax standard and pushes theoretical peak bandwidth up to an incredible 2.4 Gbps. Perhaps more importantly for power users, it's optimized for more efficient operation on crowded networks with a lot of competing traffic. Pair your motherboard with ASUS WiFi 6 routers to fully experience the networking potential of WiFi 6.

      Learn more >
      Intel WiFi 6 AX200
      2.4 Gbps
      Other wireless adapters
      0.86 Gbps

      * Actual speed varies, and depends on networking conditions.

      Back to Get the Most out of All Your Cores

      USB 3.2 Gen 2

      Numerous USB ports support high-end rigs loaded with peripherals, including two rear-panel USB Type-A connectors with fast USB 3.2 Gen 2 connectivity for compatible cases.

      Back to Build on a Solid Foundation

      Little Things Make a Big Difference

      Prime B550 series adds the nuanced details that improve every experience, from exclusive codecs that provide pristine audio quality to intuitive interface that let you customize your system to create a uniquely personal look.

      Overvoltage Protection

      World-class circuit-protecting power design

      An exclusive circuit design with built-in voltage regulators to protect your motherboard from damage caused by unexpected high-level voltages from unstable or inferior power supplies.

      DRAM Overcurrent Protection

      Short-circuit damage prevention

      Onboard resettable fuses prevent overcurrent and short-circuit damage. This extends beyond I/O ports to DRAM to safeguard the lifespan of your system and connected devices.

      Stainless-Steel Back I/O

      3X corrosion-resistance for greater durability

      Corrosion-resistant stainless-steel back I/O panels bonded with chromium oxide have a lifespan that's three times longer than ordinary panels.


      Pumped-up throughput 2.5X higher surge tolerance

      ASUS LANGuard is a hardware-level network protection feature that integrates advanced signal-coupling technology and premium anti-EMI surface-mounted capacitors to improve throughput and ensure a more reliable connection.

      Learn more


      Compatible devices and components

      The Prime B550 series provides superior compatibility with thousands of components and our Qualified Vendor List (QVL) identifies memory compatibility, giving you more choices for worry-free PC-building experiences.


      Validation hours

      Every ASUS motherboard is subjected to more than 8,000 hours of stringent tests, including burn-in, environmental, compatibility, software and safety tests to confirm their durability. ASUS reliability surpasses industry standards, ensuring that every component is designed to function flawlessly in any environment.

      Temperature and humidity tests
      Ensures components withstand extreme conditions.
      Thermal measurement tests
      Ensures that the system remains cool and stable under the heaviest loads.
      Insertion tests
      Every port and connector is put through repeated installation cycles.
      Aging tests
      Up to 48-hour aging test ensures reliability.
      Power-consumption tests
      Checked for world-class energy efficiency.
      Temperature and DC margin tests
      Ensures that the motherboard is capable of coping with voltages fluctuations caused by varying temperatures.
      Thermal-shock tests
      Ensures ability to survive temperature changes during transportation.
      Non-operation shock tests
      Built to withstand jolts that may occur during shipping.
      Burn-in tests
      Every component is checked to ensure flawless operation.
      Installation tests
      Connector placement is double-checked to ensure hassle-free installation.
      Drop tests
      Drop tests from various heights ensure durability.
      Salt and spray tests
      Tested for I/O reliability, prolonged lifespan and rust-resistance.

      Outstanding Audio

      Combined onboard features deliver elevated audio

      Intelligent design and premium hardware create audio quality unlike anything you've ever experienced.

      Audio Shielding

      Separates analog/digital signal domains, significantly reducing multi-lateral interference.

      Separate Layer for Left and Right Tracks

      Ensures minimal crosstalk between audio paths.

      Premium Japanese Capacitors

      Premium parts provide an immersive sound signature, with exceptional fidelity.

      Flawless Audio that Immerses You in the Game

      Power Pre-Regulator

      Reduces power-input noise to ensure consistent performance.

      Audio Shielding

      Separates analog/digital signal domains, significantly reducing multi-lateral interference.

      Separate Layer for Left and Right Tracks

      Ensures minimal crosstalk between audio paths.

      Integrated Amplifier

      Capable of driving high-impedance headphones, without rolling-off high or low frequencies.

      De-Pop Circuit

      Reduces start-up popping noise to all audio outputs.

      Premium Japanese Capacitors

      Premium parts provide an immersive sound signature, with exceptional fidelity.

      Armoury Crate

      Armoury Crate is a new software utility designed to give you centralized control of supported products, from a single intuitive interface. Armoury Crate provides control of settings for ASUS products, including keyboard and mouse preferences. This software even features dedicated product registration and highlight to help you stay in touch with the ASUS community.

      • Driver & Manual Download

      • Account Management

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